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Pegler, V G V, On-21332
No full textThis record was harvested from a previous catalogue system and will be withdrawn in 2025. Information in this record may be superseded or incomplete. Visit this record in UMA's new catalogue at: https://archives.library.unimelb.edu.au/nodes/view/410243Surname: PEGLER. Given Name(s) or Initials: V G V. Military Service Number or Last Known Location: ON-21332. Missing, Wounded and Prisoner of War Enquiry Card Index Number: 35742.225959
Item: [2016.0049.42512] "Pegler, V G V, On-21332
Lipopeptide overproduction by cell immobilization on iron-enriched light polymer particles
Get PDFThe study concerns surfactin and/or fengycin batch production by immobilized cells of Bacillus subtilis
ATCC 21332. Light carriers designed for a three phase inverse fluidized bed biofilm reactor (TPFIBR) were
used. With respect to the biofilm reactor development, a new support based on iron grafting onto
polypropylene foams has been proposed. A suspension solid-state grafting process was applied to graft
ferric acetylacetonate onto polypropylene (PP) foams with a density of 0.3–0.7 g/cm3. The iron contents
grafted onto PP increased with the reaction time and then it tended to level off. The iron contents at 7.5
and 10 h are 0.74 and 0.75 wt%, respectively. It was specified that the equilibrium was reached at 7.5 h.
Influence of particles on lipopeptide production was analyzed in two kinds of experiments: preliminary
colonization step of particles, followed by production step in modified culture medium (named in this
work colonization step) or direct addition of pellets in culturemedium (named production step). All PP+
iron pellets promoted biomass enhancement. The production yield was modified for all types of PP
supports, containing respectively 0, 0.35 and 0.75% of iron. The immobilized cultures produced 2.09–4.3
times more biosurfactants than planktonic cells. In production experiments addition of carriers seemed
tomodify the ratio between surfactin and fengycin with an enhancement of the fengycin production. The
highest concentration of fengycin was obtained with addition of pellets containing 0.35% of iron
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Get PDF“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Get PDFWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Antimicrobial protein produced by Bacillus subtilis ATCC 21332 in the presence of Allium sativum
Get PDFIntroduction: Proteins levels produced by bacteria may be increased in stressful surroundings, such as in the presence of antibiotics. It appears that many antimicrobial agents or antibiotics, when used at low concentrations, have in common the ability to activate or repress gene transcription, which is distinct from their inhibitory effect. There have been comparatively few studies on the potential of antibiotics or natural compounds in nature as a specific chemical signal that can trigger a variety of biological functions. Objective: To study the effect of Allium sativum in regulating proteins production by Bacillus subtilis ATCC 21332. Methods: The bacteria cells were exposed to the A. sativum at concentration of 0.025 MIC for 24 h. The extracellular proteins were then isolated and screening for antimicrobial activity before being further analyzed by using Sodium Dodecyl Sulfate Polyacrylamide Gel Electrophoresis (SDS-PAGE) and Liquid Chromatography-Tandem Mass Spectrometry (LC-MS/MS). Results & Discussion: The isolated extracellular proteins showed antimicrobial activity against selected Gram-positive and Gram-negative bacteria. Proteins profile showed that two new bands with approximate sizes of 51.36 kDA and 9.74 kDA were appeared for the treated bacteria with A. sativum. LC-MS/MS analysis revealed that four and two possible proteins were identified for each of isolated proteins with approximate sizes of 51.36 kDA and 9.74 kDA. Conclusion: B. subtilis ATCC 21332 in stressful condition with the presence of A. sativum at low concentration (0.025 MIC) could induce the production of bioactive protein with antimicrobial activity
Studies on the biosynthesis of surfactin, a lipopeptide antibiotic from Bacillus subtilis ATCC 21332
No full textAbstractThe biosynthesis of the lipopeptide antibiotic surfactin was studied in whole cells of Bacillus subtilis ATCC 21332 which incorporate 14C-labeled precursor amino acids directly into the product. [14C]Acetate appeared in the fatty acid portion of surfactin and was also partially converted into leucine. An enzyme was isolated and partially purified from a cell-free extract of the bacillus which catalyzes ATP-Pi-exchange reactions which are mediated by the amino acid components of surfactin. This activation pattern is consistent with a peptide synthesizing multienzyme which activates its substrate amino acids simultaneously as reactive aminoacyl phosphates
Dispelling the Myths Behind First-author Citation Counts
Get PDFWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
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